Method of and arrangement for the continuous straightening by stretching of bands



Sept. 17, 1963 R. RAHN 3,103,964

METHOD OF AND ARRANGEMENT FOR THE CONTINUOUS STRAIGHTENING BY STRETCHING OF BANDS Filed Aug. 10. 1960 2 Sheets-Sheet 1 Sept. 17, 1963 R. RAHN 3,103,964

METHOD OF AND ARRANGEMENT FOR THE CONTINUOUS STRAIGHTENING BY STRETCHING 0F BANDS Filed Aug. 10, 1960 2 Sheets-Sheet 2 M/VENI'OE a ifiilllllllll United States Patent'O 3,103,964 METHOD OF AND ARRANGEMENT FOR THE CONTENUOUS STRAIGHTENING BY STRETGH- ING F BANDS Richard Rahn, Dusseldorf, Germany, assignor to Schloemann Aktiengesellschaft, Dusseldorf, Germany Filed Aug. 10, 1960, Ser. No. 48,749 Claims priority, application Germany Aug. 17, 1959 7 Ctaims. (til. 153-35) In order to straighten sheets and bands, so-called straightening rolls are frequently used, in which the material to be straightened runs through a system of driven straightening rolls, which consists of a series of lower rolls and a series of upper adjustable straightening rolls which are staggered with respect to the lower straighten ing rolls. In order to obtain the partially plastic deformation required for the straightening of the material, the diameters of the rolls must not exceed a definite amount, which leads to dilficulties, more particularly in the case of thin sheets.

Better straightening results may generally be obtained on stretching machines, on which the material is stretched beyond its elastic limit. The usual stretching benches can only take material of limited length, which assumes a dividing up of the material before the stretching. The clamping and releasing of the material as well as the stretching take up relatively much time, for which reason the throughput of the stretching benches is correspondingly slow. The ends of the material, set in the gripping jaws, become damaged during stretching and have to be cut away, causing considerable waste. Arrangements are also known for the semi-continuous or fully continuous straightening by stretching. The tension required for stretching the band is in this arrangement applied by a winch drum or a roll stand. At the other end the band is held in a roller brake round which the band is wound in the form of an S.

It is more particularly diflicult, however, in the case of thin bands, to produce the requisite holding power in the roller brake unit. If the stretching operation is to take place continuously, it is also necessary that the pulling arrangement shall always apply the whole stretching force, so that .a correspondingly efficient drive is required. In some circumstances a portion of this output can be recovered, but this involves considerable constructional expenditure.

A simpler method, in which with similar arrangements a band of any thickness can be continuously stretched, is the object of the invention.

The invention consists in inserting in one of the last convolutions of -a band wound or to be wound into a coil, but not the very last convolution, preferably the last but one, a roller for drawing this convolution away from the coil, which during the unwinding or winding up of the band from off or on to the winch drum causes the requisite stretching force to be produced in the band, whilst any convolutions located outside the convolution thus tensioned are passed around the coil, and also around deflecting rollers located outside the tensioned convolution, the tension in the free end portion of the band being considerably reduced by the peripheral friction of the outermost convolution of the band against the adjacent convolution located within it.

For carrying this method into effect according to the invention, an arrangement is proposed, in which there are correlated with a winch drum, parallel to the axis, a roller which is movable radially in relation to it and is impelled with about double the stretching force away from it. Defiecting rollers are also provided, which are supported with their axes parallel to that of the winch drum.

3,103 ,964 Patented Sept. 17, 1963 The arrangement according to the invention can be operated separately from the rolling mill or from the rolling mill auxiliary arrangements, in which case it may be associated with a winding up reel which takes up the band straightened by stretching. The winch drum of the arrangement according to the invention then serves as an unwinding reel.

According to a further feature of the invention the arrangement may be disposed before or more especially behind a rolling mill, the winch drum of the arrangement acting in the first case as an unwinding reel and in the second case as a Winding up reel. The arrangement in front of a rolling mill is only suitable, if through the following rolling operation no fresh internal stresses in the band, which would make a fresh straightening necessary, can occur, that is before finishing or polishing rolls.

Finally, the arrangement may, according to a further f ature of the invention, be also used with rolling mill auxiliaries, for instance shears. In such a case the arrangement according to the invention must be provided with driving gear which, when the arrangement is for instance used in front of shears, draws the band off the winch drum of the arrangement, then acting as unwinding reel.

Further details of the invention may be taken from the drawings and the description of constructional examples.

The drawings show in:

FIGURE 1 a diagrammatic representation, in

FIGURE 2 a constructional example in front elevation, and in FIGURE 3 a constructional example in plan view.

Further construction-a1 examples are shown in FIG- URES 4 and 5 in diagrammatic representation.

In the constructional example according to FIGURES 1 to .3 the reference numeral 1 indicates a winch drum acting as a unwinding reel and the numeral 2 a winch drum acting as winding up reel. Each of these winch drums is supported in a bearing block 3 or 4. The winch drum 3 is braked through gearing 5 by a braking motor 7, and the winch drum 4 is driven through gearing 6 by a driving motor 8. By way of a roller track 9 and a lift arrangement 10 the band bundle 25 may be brought before the winch drum 1, and slid on to it. To facilitate this operation the unwinding drum may advantageously be of the kind disclosed in application Serial No. 686,181, filed September 25, 1957, in which the winch drum comprises radially displaceable segments, whereby its periphery can be enlarged and reduced at will. The two outer band convolutions 11 and 12 of the bundle placed upon the winch drum 1 are thereupon loosened, so that deflecting rollers 13 can be introduced into the outermost convolution 11, and into the last convolution but one, 12, a tension roller 14, which is in a position very much nearer the winch drum, can be introduced. The free band end 15 is then passed round the deflecting roller 16 and fixed at the winch drum 2. The insertion of the rollers 13 and 14 into the existing band loops loosened for the purpose, necessitates these rollers being axially slidable. The rollers 13 and 14 may on the other hand be made axially non-displaceable, but in that case the band end has to be passed suitably round the tensioning roller 14, then round the Winch drum "1 again, then round the deflecting rollers 13, then round the winch drum again, and then over one roller 13 and under the roller 16 to the winch drum 2.

The rollers 13, 14 and 1 6 are supported in the two frame members of a roller chair '17, the roller 14 being displaceable in guides 18 by means of pistons guided in pressure cylinders 19. One frame member of the roller chair -17 bears with the supporting wall 20 against the bearing block 3 of the winch drum 2. The other frame member of the roller chair 17 is provided with a strut areas-3a 23 capable of pivoting about a pin 22, one forked end of this strut bearing against a journal pin 24 at the free end of the winch drum 1, so that the roller chair 17 and the free end of the winch drum 1 are braced against one another. in order to be able to place a fresh bond bundle on to the winch drum 1 the strut 23 is swung away.

After the band convolutions 11 and 12 and the bud end 15 have been put under stress again by turning the winch drum 1 backwards or turning the winch drum 2 forwards, or both, the pull roller 14 is drawn away from the winch drum 1 by means of the pistons guided in the pressure cylinders 19, with such force (see arrow in FIGURE 1) that in the band sections bearing against the pull roller 14 the stretching force required for straightening the band sections is created. By winding the band on to the winch drum 2, by means of the driving motor 8, while at the same time slightly braking the winch drum 1 by means of the braking motor 7, all subsequent band sections will be continuously straightened by stretching. The pull roller 14 must be movable in the guides 18 to such a degree that it can always compensate for the elastic and permanent extensions of the band under the stretching force.

In the constructional example according to FIGURE 4, the arrangement according to the invention, which consists of the winch drum 30, in this case driven as a winding up reel, the pull roller 31 and the deflecting rollers 32, follows a rolling mill 33. Preceding the rolling mill there is an unwinding reel 34. For guiding the hand through the rolling mill, guide rollers 35 and 36 are provided. Initially the leading end of the band from the unwinding reel 34 is passed over the guide pulley 35, through the rolling mill 33, over the guide pulley 36, round the under side of the winding-up reel 30, round the deflecting rollers 32, round the winding up reel 33 but within the part already passing round this reel, and round the pull roller 31, and is then attached to the periphery of the winding-up reel 30. The tension is applied to the pull roller in the same way as in the other embodiments.

In the case of the constructional example according to FIGURE 5, on the other hand, the arrangement according to the invention of shears is provided. The band runs off the winch drum 4!) operated as a winding otf reel, runs with its last convolution but one round the pull roller 41, is stretched by it beyond the elastic limit, runs with its last convolution round the guiding rollers 42 and is drawn off by the pair of driving rollers 43 and conveyed by a pair of driving rollers 44 to the shears 45, by which it is subdivided into plates of the desired length.

I claim:

1. A method for the continuous stretch-straightening of bands, wherein a band is drawn from a braked unwinding reel on to a positively driven winding-up reel,

4 comprising: applying tension to a convolution which is nearly but not quite the outermost convolution of the band on the unwinding reel, and passing any convolu tions located outside the convolution thus tensioned over deflecting rollers, and also over and in contact with the tensioned convolution where it bears upon the reel.

2. A method for the continuous stretch-straightening of bands as claimed in claim 1, the tensioned convolution being the outermost convolution but one on the unwinding reel.

3. Apparatus for the continuous stretch-straightening of bands, comprising: a winch drum, a roller, with its axis parallel to that of the winch drum, the said roller being adapted to move radially in relation to the winch drum, means for impelling the said roller away from the winch drum with a force about twice as great as the required stretching force, and deflecting rollers located farther from the winch drum than the radially movable roller journalled one on each side of the plane containing the axes of the winch drum and of the axially movable roller, with their axes parallel to that of the winch drum.

4. Apparatus for the continuous stretch-straighening of bands as claimed in claim 3, in combination with a winding-up reel, in front of which the stretch-straightening apparatus is located, the winch drum of the stretchstraightening apparatus acting as an unwinding reel.

5. Apparatus for the continuous stretch-straightening of bands as claimed in claim 3, in combination with a rolling mill, in front of which the stretch-straightening apparatus is located, the winch drum of the stretchstraightening apparatus acting as an unwinding reel, and the rolling mill serving to draw the band oil the unwinding reel.

6. Apparatus for the continuous stretch-straightening of bands as claimed in claim 3, in combination with a rolling mill behind which the stretch-straightening apparatus is located, the winch drum of the stretch-straightenin g apparatus acting as a winding-up reel.

7. Apparatus for the continuous stretch-straightening of bands as claimed in claim 3, in combination with shears located behind the stretch-straightening apparatus, the winch drum of the stretch-straightening apparatus acting as an unwinding reel, and the apparatus further comprising, before the shears, positively driven rollers for drawing the band off the winch drum.

References (Iited in the file of this patent UNITED STATES PATENTS 1,964,874 Faukboner July 3, 1934 2,327,103 Gude Aug. 17, 1943 2,348,539 Harper May 9, 1944 2,432,828 Stone Dec. 16, 1947 2,653,643 Miller Sept. 29, 1953 

1. A METHOD FOR THE CONTINUOUS STRETCH-STRAIGHTENING OF BANDS, WHEREIN A BAND IS DRAWN FROM A BRAKED UNWINDING REEL ON TO A POSITIVELY DRIVEN WINDING-UP REEL, COMPRISING: APPLYING TENSION TO A CONVOLUTION WHICH IS NEARLY BUT NOT QUITE THE OUTERMOST CONVOLUTION OF THE BAND ON THE UNWINDING REEL, AND PASSING ANY CONVOLUTIONS LOCATED OUTSIDE THE CONVOLUTION THUS TENSIONED OVER DEFLECTING ROLLERS, AND ALSO OVER AND IN CONTACT WITH THE TENSIONED CONVOLUTION WHERE IT BEARS UPON THE REEL. 